Hello everyone !
Well, this subject, I have already mentioned it several times, giving my personal explanation, but it seems that it is too simple to be taken seriously, and yet ...
Up to now, 99,99% of water doping has been supplied with steam by more or less large bubblers.
You must now know what I think of these machines, concerning their thermal inertia, which in the case of a variable load regime (car) induces a more or less pronounced phase shift between the production of steam and the engine needs ...
I explain on my site that a car with pantone / bubbler which has just taken a hill sees its steam production being at its maximum at the top, which means that when it attacks a descent just after, it ends up with a engine brake reduced.
The question is: why?
The first thing that comes to mind is that the engine sucks a hot aerosol in its intake, which a priori represents less material (air + steam) than the same volume at a lower temperature.
For example, we know that a turbo is followed by a cooling system intended to improve the boosting of the combustion chamber, therefore the final pressure at TDC, that is to say precisely the opposite of what happens with the pantone downhill.
The second thing, more hypothetical, is that the electrified aerosol (since it is still produced) will always be in conditions allowing it to crack, since there is always a minimum injection of diesel, so a front flame to initiate the reaction, and this gain in engine torque will therefore be given undesirably by the pantone ...
These are among other reasons that led me to the idea of GV.
Since there is a request for testimony, and we have the chance, Didier and I, to live in a mountainous region, I will give you two:
Mine first, with the 205. I did not notice any engine brake problem on the descents that I know well, speed between 50 and 90 km / h, third or fourth depending on the case, I do not use more my brake pads as before pantone and I use the same ratios in the same places ...
The case of Didier, with the merco. He indicated to me (and I noted it during our joint trips) that he had a slight and brief loss of engine braking, sometimes accompanied by a fleeting "taking of revolutions" of the engine at the time of declutching (in downshifting ), this phenomenon does not cause any particular gene, except that it has had to modify a little his way of driving, by anticipating this transitory phenomenon.
I say transient, because during a descent, it does not need to apply the brakes more than before, and it also keeps the same reports, under identical conditions.
All this to say that in the case of the engine brake, (for having measured it) the temperature of the mill exhaust gases drops very quickly and very low (up to 70 ° C). Under these conditions, I saw the temperature of the steam, at the outlet of the steam generator drop to 40 ° C, depending on the case.
Therefore, the production of steam falling, the overproduction of the chambers is partially canceled, enough in any case not to harm the engine brake
It's a bit like the story of the magnetization of the reactor rod, you have to make the distinction between the causes and the consequences, and as regards the engine brake, the GV allows to circumvent the problem (even if the explanations are not the right ones, the facts and the experimentation are there to demonstrate it)
I hope to have been clear,
See you soon
Michel
We were on the brink, but we made a big step forward ...